glibc/SOURCES/glibc-rh1817513-99.patch
2021-09-16 08:47:57 +00:00

95 lines
2.5 KiB
Diff

commit 647103ea3a2aae2e6791b3bebe9e33eedc168102
Author: Florian Weimer <fweimer@redhat.com>
Date: Fri Oct 9 10:13:14 2020 +0200
elf: Enhance ld.so --help to print HWCAP subdirectories
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
diff --git a/elf/dl-usage.c b/elf/dl-usage.c
index 8d39bc9d5442bc59..c07f43835bd771cf 100644
--- a/elf/dl-usage.c
+++ b/elf/dl-usage.c
@@ -22,6 +22,8 @@
#include <unistd.h>
#include "version.h"
+#include <dl-hwcaps.h>
+
void
_dl_usage (const char *argv0, const char *wrong_option)
{
@@ -101,6 +103,65 @@ print_search_path_for_help (struct dl_main_state *state)
print_search_path_for_help_1 (__rtld_search_dirs.dirs);
}
+/* Helper function for printing flags associated with a HWCAP name. */
+static void
+print_hwcap_1 (bool *first, bool active, const char *label)
+{
+ if (active)
+ {
+ if (*first)
+ {
+ _dl_printf (" (");
+ *first = false;
+ }
+ else
+ _dl_printf (", ");
+ _dl_printf ("%s", label);
+ }
+}
+
+/* Called after a series of print_hwcap_1 calls to emit the line
+ terminator. */
+static void
+print_hwcap_1_finish (bool *first)
+{
+ if (*first)
+ _dl_printf ("\n");
+ else
+ _dl_printf (")\n");
+}
+
+/* Write a list of hwcap subdirectories to standard output. See
+ _dl_important_hwcaps in dl-hwcaps.c. */
+static void
+print_legacy_hwcap_directories (void)
+{
+ _dl_printf ("\n\
+Legacy HWCAP subdirectories under library search path directories:\n");
+
+ const char *platform = GLRO (dl_platform);
+ if (platform != NULL)
+ _dl_printf (" %s (AT_PLATFORM; supported, searched)\n", platform);
+
+ _dl_printf (" tls (supported, searched)\n");
+
+ uint64_t hwcap_mask = GET_HWCAP_MASK();
+ uint64_t searched = GLRO (dl_hwcap) & hwcap_mask;
+ for (int n = 63; n >= 0; --n)
+ {
+ uint64_t bit = 1ULL << n;
+ if (HWCAP_IMPORTANT & bit)
+ {
+ _dl_printf (" %s", _dl_hwcap_string (n));
+ bool first = true;
+ print_hwcap_1 (&first, GLRO (dl_hwcap) & bit, "supported");
+ print_hwcap_1 (&first, !(hwcap_mask & bit), "masked");
+ print_hwcap_1 (&first, searched & bit, "searched");
+ print_hwcap_1_finish (&first);
+ }
+ }
+}
+
void
_dl_help (const char *argv0, struct dl_main_state *state)
{
@@ -136,5 +197,6 @@ This program interpreter self-identifies as: " RTLD "\n\
",
argv0);
print_search_path_for_help (state);
+ print_legacy_hwcap_directories ();
_exit (EXIT_SUCCESS);
}